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'86 K75 gas tank breather line routing?

58fleetside

New member
'86 K75..Does the breather line at the front rt of the gas tank rout under or over the frame spine? Mine is over and seems like it gets compressed by the tank.

Thanks, Stephen
 
Under - from up through that whole big mess of wiring. It should go almost straight up onto the stub pipe.

Better yet - get one Air Accumulator, Part # 16 13 2 307 467 which is a small squarish shaped plastic funnel which clips on the frame under the vent and drain hose stub pipes, eliminating the connection of those hoses to the tank completely.
 
Better yet - get one Air Accumulator, Part # 16 13 2 307 467 which is a small squarish shaped plastic funnel which clips on the frame under the vent and drain hose stub pipes, eliminating the connection of those hoses to the tank completely.


If you go with the Air Accumulator (highly recommended), you must be sure to cap where the fuel tank vent hose goes into the top of the block just below the fan or you will have a major vacuum leak.



:dance:dance:dance
 
If you go with the Air Accumulator (highly recommended), you must be sure to cap where the fuel tank vent hose goes into the top of the block just below the fan or you will have a major vacuum leak.



:dance:dance:dance

If you have a K75 which still has the fuel tank vent connected to the stub pipe to the engine block (with the little valve) you should disconnect it, cap the stub pipe, and reroute the vent hose to behind the right footpeg. If you do, and you don't, and you ever fill the tank and park in the Sun you will dump raw gasoline into the crankcase. That dilutes the oil. That destroys bearings and other things.

'I bought my first K75 in March, 1986. The dealer did the modifications at the 600 mile service two days after I bought the bike.
 
My K75 had the air accumulator when I bought it used 7 years ago. It does make it easier to remove the fuel tank, but I found that I was always smelling gas fumes, especially on a warm day ( I have a black tank ). The vapors just come up from under the tank. The accumulator would drain liquids out through the hose, but the vapors just went anywhere. I got real inventive and made a Y - actually more of an F- to tie the 2 vent tubes together and use the one drain hose to move liquids and vapors down by the footpeg. Perfect solution-not. The fumes instead of going down would come up the fuel cap water drain and I still had gas smell. I finally just put a hose on each vent and routed them down like the 1 original. They are a little more difficult to hook up when installing the fuel tank and I have to be careful not to kink them when the tank is seated in the rubber grommets. So far so good.
 
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